Warm Air Helped Make 2017 Ozone Hole Smallest Since 1988 (image) NASA/Goddard Space Flight Center Share Print E-Mail Caption At its peak on Sept. 11, 2016, the ozone hole extended across an area nearly two and a half times the size of the continental United States. The purple and blue colors are areas with the least ozone. Credit Credits: NASA/NASA Ozone Watch/Katy Mersmann Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.